when steeping, go for 20-30 mins. you're not extracting fermentables, only colors and flavors.
S-33 isn't a bad yeast, however Fermentis has some other dry ale yeast strains that might work better. S-04 is one that comes to mind, aimed at English ale styles. S-33 is listed as their 'high tolerance, Belgian style' strain.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10